The ability of infants between birth and 1 year of age to utilize starch will be determined. The development of salivary and pancreatic alpha-amylase and intestinal glucoamylase will be followed. Samples of saliva, duodenal fluid and duodenal mucosa will be obtained from infants. Pancreatic and small intestinal samples will be obtained from autopsy materials. Pancreatic response to pancreozymin-secretin in infants at appropriate ages will be evaluated. Starches will be fed orally and the degradation products from duodenal content will be amalyzed by thin layer chromotography and results correlated with the development of anylase and glucoamylase. Duodenal amylase activities during development will be separated into salivary and pancreatic amylase by electrophoresis and evaluated to establish the relative importance of these amylases in the digestion of starch. To define the mechanism which results in low amylase activity in the duodenal fluid in newborns, we will take 2 approaches: 1) to measure immunoreactive but enzymatically inactive amylases with an antiamylase sera; 2) to use dispersed pancreatic acini from rats as a model to measure their response to secretogogues that act via cAMP (eg. VIP) and CA ++ outflux (eg. pancreozymin) at various perinatal ages. This is to assess the possible deficiency of response to these secretogogues. Clinically, we will compare premature and small for date infants to full term babies in their ability to digest starch. We will examine the effect of various feeding methods and diets (eg. cow's milk base, soy bean base and elemental formula and total parenteral nutrition) on the development of the pancreatic and salivary amylase. Adaptative changes in salivary and pancreatic amylases will also be evaluated using high starch diets. Lastly, the effect of intractable diarrhea of infancy, and short bowel syndrome on starch digestion will be looked at.